Since I installed the dasc - I did not change the injectors... so unfortunatelly I can not help with any possible snags, but looking at one of my old pics (below), I can not figure out which injector are you having an issue with.
It seems they are all accessible - just make you sure you disconect the baterry (i.e. fuel pump) & bleed the system (overflow) before you start pulling the injectors.
Can you point out the problem area below?